Reactors for the treatment of a sample medium are used for example for carrying out bioprocesses, meaning the obtainment of products by biochemical reactions. If such bioprocesses are to be used on an industrial scale, the sequence of the bioprocess must be precisely investigated in advance, in order to accomplish the highest possible efficiency of the bioprocess by choosing suitable process parameters. This procedure is referred to as upstream processing.
An installation which allows the bioprocess to be carried out under laboratory conditions is required for the upstream processing. Such an installation, referred to as a table-top fermenter, is offered for example by Infors AG, who on Oct. 25, 2001 described their product under the model name “Sixfors” on the Internet page www.infors.ch/d/d5a.htm. According to the illustration published on this Internet page, “Sixfors” comprises a base station, on which a bioprocess can be carried out simultaneously in six beakers, under modified conditions in each case. As disclosed by the text describing “Sixfors”, these beakers have agitating shaft inserts (which can be seen in the illustration). Additionally provided are drives with a magnetic coupling, which can move agitating magnets which are shown in the drawing and are located on the bottom of the beakers.
The two agitating devices mentioned provide constant circulation of the reaction fluid while the bioprocess is being conducted, whereby a quasi steady-state bioprocess can be maintained. This process largely corresponds to the conditions during industrial-scale use. The quasi steady state is referred to as fed-batch, meaning that the bioprocess is maintained by constant feeding of reaction fluid on the one hand and removal of the reaction product on the other hand.